The present invention relates to printers and, more particularly, to printers depositing materials for print images on sheets of paper selected from a stack of cut-sheet paper.
The use of personal computers and, correspondingly, desk top printers controlled in part by such computers has increased very rapidly over the last several years. Many different printing technologies have been developed for these printers beyond that used in the impact printers initially performing in this role, including ink jet, thermal wax transfer and thermal dye sublimation printing technologies.
As usage of personal computers has grown, there has been a corresponding increase in the demand for relatively compact printers that are expected to print relatively modest numbers of documents a day. In addition, the printer output often comprises private or business letters, or office memorandums, which are sent to single or relatively few addressees. In these circumstances, there has been an increased demand for printers which print on cut-sheet paper, one sheet at a time, rather than printing on stock from rolls or the like.
One manner in which the need to supply individual sheets to the printing process portions of such single-sheet printers has been met is through the use of cassette trays in which a stack of cut-sheet paper is placed as a store for the printer. Typically, such a cassette tray has a pair of corner tabs over corners of the stacked paper at the leading edge of such a tray as it is intended to be inserted into the printer. These corner tabs are provided parallel with the major surface of the stacked paper. A drive roller, in contact with the top sheet of the stack, selectively forces, as needed, such a top sheet forward to thereby force the leading corners of that sheet against these corner tabs causing the sheet to buckle and then snap forward over the tabs to separate the sheet from those underlying in the stack below.
Such cassette trays operate quite well, but require a significant amount of time to be reloaded with a stack of paper. First, the cassette tray must be removed from the printer. After the stack of cut-sheet paper has been inserted therein, the cassette must be reinserted into the recorder and properly engaged with whatever holding arrangement has been provided. Thus, there is a desire to increase the speed of the paper reloading operation in a printer, as well as to avoid the expense of a separate cassette tray.